Tool for forming asbestos linings and the like

ABSTRACT

A tool sized to be rotated and moved lengthwise through a cylindrical chamber to form a cement-asbestos composition into a tubular lining around the walls of the chamber. The composition is fed to the tool by air pressure and is directed in a plurality of streams circumferentially spaced around the outer periphery of the tool toward the inner periphery of the chamber. The outer periphery of the tool is shaped to compact the composition against the inner periphery of the chamber as the tool is rotated and moved lengthwise.

United States Patent 1 1 Brown 1 1 Mar. 27, 1973 1541 TOOL FOR FORMING ASBESTOS 2,204,020 6/1940 La Due ..25/36 LININGS AND THE LIKE 2,220,975 11 1940 ORahilly ..25/36 [75] Inventor: Lester F. Brown, Lubbock, Tex. Primary ExamineFJ' Spencer Overholser [73] Assignee: Standard Concrete Pipe Company, Assist! Examiner-John s-Bfown Inc Lubbock, AttrneyDunlap, Laney & Hessin [21] Appl.No.: 773,858 A tool sized to be rotated and moved lengthwise through a cylindrical chamber to form a cement- 52 us. 01 ..425/262, 425/460 asbesws cmpositin a tubular "fling around 51 Int. c1. ..B28b 19/00 Of chamber- The compcsitim is fed the Search" tOOl air pressure and IS directed in a plurality Of /38425/262460 streams circumferentially spaced around the outer periphery of the tool toward the inner periphery of the References Cited chamber. The outer periphery of the tool is shaped to compact the composition against the inner periphery UNITED STATES PATENTS of the chamber as the tool is rotated and moved lengthwise. 3,106,006 10/1963 Perovich ..25/38 921,142 5/1909 Myers et al ..25/36 23 Claims, 16 Drawing Figures 0 ll O PATEMEUMARNIQB SHEET 1 [IF 4 fla :ElET-Ei INVENTOR. Zr-sra? E dean u 7 m/ers TOOL FOR FORMING ASBESTOS LININGS AND THE LIKE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to improvements in devices for forming tubular linings, and more particularly, but not by way of limitation, to an improved tool for forming a cement-asbestos composition into a liner for a tubular '10 member.

2. Description of the Prior Art In the past, linings for tubular members have, in the main, been formed from a slurry of neat cement, rather than a cement-asbestos composition. The slurry is usually placed in the pipe or tube to be lined, and either the pipe or tube is rotated to spread the slurry by centrifugal force, or the slurry is simply trowled around the inner surface of the pipe or tubing. In either event, little compaction is obtained and the lining is not effectively adhered to the pipe or tubing. Further, the use ofa slurry results in a lining of relatively low strength due to excess air and water pore space.

The strength of cement drops as a semi-logarithmic function of the water-cement ratio. If by means of pressure, the mixture is compacted so as to eliminate all pores, its strength is found to be of measurable order.

SUMMARY OF THE INVENTION This invention contemplates a novel tool particularly suitable for forming a compactable plastic material, such as a cement-asbestos composition having a low water content, into a liner for a tubular member. The tool comprises a generally cylindrical body, with the outer periphery of the body being shaped to provide a plurality of surfaces arranged side-by-side circumferentially around the body. Each of said surfaces is progressively increased in radius relative to the center line of the tool from one side thereof to the other, and the surfaces are arranged with the smallest radius side of each surface around the body in the direction the body is rotated during use. Said surfaces are also tapered radially inward from the medial portion of the body to one end of the body. The tool further includes a feed nozzle at the tapered end of the body at the smallest radius side of each of said surfaces to direct streams of the plastic material radially outward toward the walls of the chamber through which the tool is moved in a position to be compacted against the walls of the cylindrical chamber by said surfaces as the tool is rotated and moved lengthwise through the chamber.

An object of the invention is to increase the hydrostatic and structural strength of tubular linings when constructed with a cement-asbestos composition.

A further object of the invention is to provide a lining tool which is simple in construction, has a minimum of wear during use, and requires a minimum of maintenance.

A still further object of the invention is to provide a tool particularly suited for lining tubular members which forms a composition into a lining by compacting the material, and wherein the density of the lining exceeds any known in industry.

Another object of the invention is to provide a dense lining for tubular products with a tool that can compact a cement-asbestos mixture having a water to cementasbestos ratio of 0.125.

A Other objects and advantages of the invention will be evident from the following detailed description, when read in conjunction with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a plan view of a tool constructed in accordance with this invention.

FIG. 2 is a vertical sectional view through the tool as taken along lines 2-2 of FIG. 1.

FIG. 3 is a vertical sectional view through the tool taken along the lines 33 of FIG. 1.

FIG. 4 is another sectional view of the tool as taken along lines 44 of FIG. 2.

FIG. 5 is a vertical sectional view through a pipe showing use of the tool in forming a lining in the pipe.

FIG. 6 is a sectional view as taken along lines 6-6 of FIG. 5.

FIG. 7 is a schematic vertical sectional view through a mixer which may be used in mixing the materials used to form a tubular lining with the present tool.

FIG. 8 is an elevational view, partially in section, of a modified tool constructed in accordance with this invention.

FIG. 9 is a sectional view taken along lines 9-9 of FIG. 8.

FIG. 10 is a sectional view taken along lines 10-10- of FIG. 8.

FIG. 11 is a sectional view taken along lines 1ll1 of FIG. 8.

FIG. 12 is an elevational view, partially in section, of another tool constructed in accordance with this invention, illustrating the tool in use.

FIG. 13 is a sectional view taken along lines 13-l3 of FIG. 12.

FIG. 14 is a sectional view taken along lines 14l4 of FIG. 12.

FIG. 15 is an elevational view, partially in section, of still another tool constructed in accordance with this invention.

FIG. 16 is a sectional view taken along lines 16-16 of FIG. 15.

DESCRIPTION OF THE PREFERRED EMBODIMENtS EMBODIMENTS Referring to the drawings in detail, and particularly FIGS. 1 through 4, reference character 10 generally designates a tool constructed in accordance with this invention which basically comprises a generally cylindrical body 12 adapted to be rotated and moved lengthwise by a drive pipe 14.

In a form of the tool 10 particularly suited for relatively large diameter work, the body 12 comprises four identical segments or sections 16 which may be conveniently formed from a piece of heavy wall pipe cut lengthwise into quadrants. Each segment 16 has a plurality of reinforcing plates 18 welded in spaced relation along the length of the segment, including the opposite ends of the segment. As shown most clearly in FIG. 4, the reinforcing plates 18 of each segment 16 are cut at their inner edges 20 along the arc of a circle. Supporting plates 22 are bolted to the end reinforcing plates 18 of all of the segments 16 to hold the segments 16 in the desired offset or staggered relation as illustrated clearly in FIGS. 1 and 4. Also, spacer bars 24 are welded between the adjacent sides of the adjacent segments 16 (FlG. 4) to further assist in holding the segments in the desired relation.

As will be observed from the drawing, the segments l6 are supported in a non-symmetrical relationship with respect to the center line through the tool, such that the outer surface 26 of each segment 16 has a radius progressively increasing circumferentially of the tool from one side of the segment to the other with respect to the center line of the tool. The smaller radius side'28 of each surface 26 is positioned adjacent the larger radius side 30 of the surface 26 of one of the adjacent segments 16. Further, and as shown in FIGS. 2 and 3, the outer peripheral surface 26 of each segment 16 is tapered radially inward from the medial portion 32 of the body 12 to the upper end 34 of the body. Similarly, the surface 26 of each segment 16 is tapered radially inward from a lower medial portion of the body 12 to the lower end 36 of the body. The opposite ends of each surface 26 and the respective opposite ends 34 and 36 of the body 12 are preferably coterminous.

The drive pipe 14 is connected to the body 12, in alignment with the centerline of the body 12, by means of a square shaft 38 suitably secured to the drive pipe 14, as by welding, extending through square-shaped apertures 40 in the supporting plates 22 at the opposite ends of the body 12. A suitable nut 42 is threaded on the end of the shaft 38 opposite the drive pipe 14 to hold the body 12 tightly against the end 43 of the drive pipe 14 and maintain the drive pipe and body assembled, such that the body 12 may be rotated and moved lengthwise by rotation and lengthwise movement of the drive pipe 14.

Four couplings 44 are suitably secured in the walls of the drive pipe 14 in spaced relation from the adjacent end 34 of the body 12 in such a manner that the couplings 44 communicate with the interior of the drive pipe 14. A flow divider 46 is secured in the drive pipe 14 between the couplings 44 and the adjacent upper end 34 of the body 12 to direct the material to be applied by the tool from the interior of the drive pipe 14 through the couplings 44. A conduit 48 connects each coupling 44 to a respective tubular feed nozzle 50 secured in the end 34 of the body 12. The conduits 48 are preferably flexible to prevent rupture thereof in the event the drive pipe 14 may be rotated to a slight degree with respect to the body 12 during operation of the tool, as will be set forth below.

Each feed nozzle 50 is positioned above one of the blocks 24 at the smaller radius side 28 of one of the segments 16, such that four of the feed nozzles 50 are provided in equally spaced, circumferential relation around the body 12. Each feed nozzle 50 is suitably secured to the respective segment 16 and spacer block 24, as by welding, and the discharge end 52 of each nozzle 50 is coterminous with the respective smaller radius side 28 of the respective segment 16. It may also be observed in FlG. 2 that each feed nozzle 50 is positioned at an angle of about 45 with respect to the center line through the tool to direct the material to be formed radially outwardly from the body 12 and generally to a position opposite the medial portion 32 of the body 12.

A tubular shield 53, having an outer diameter substantially equal to the maximum outer diameter of the upper end 34 of the body 12, is welded to the upper end of the body 12 and extends concentrically around the drive pipe 14 for purposes to be described.

The preferred composition to be applied or formed with the tool 10 comprises percent (plus or minus 10 percent) Portland cement, by weight, and 30 percent (plus or minus 10 percent) Chrysotile asbestos, by weight, thoroughly mixed with water to an extent such that the ratio of water to the dry cement and asbestos together is about 0.125, measured on a weight basis.

The cement may be of substantially any suitable type,

such as that previously used in forming asbestos pipe,

highway paving or in cementing oil wells. The asbestos may be of any desired grade, but is preferably not a major portion of fines, and the maximum fiber length is preferably appreciably less than the wall thickness of the tubular member to be formed with the tool 10. Asbestos in Grade 5D, according to the Standard Canadian Chrysotile Asbestos Classification, has been found quite suitable for forming a lining having a wall thickness of about 0.6 to 2 inches.

The composition is preferably prepared by first mixing the dry cement and asbestos in an auger-type mixer as schematically illustrated in FIG. 7. Such a mixer comprises an outer shell 54 having a suitable inlet 56 in the top thereof and a double slanted bottom 58. Discharge and clean-out doors 59 are provided in the bottom 58. An inner shell 60 is suitably supported'in the outer shell 54 by brackets 61 to provide an annulus 62 there between, with the upper and lower ends of the inner shell 60 terminating short of the top and bottom of the outer shell 54. A cut-flite auger 64 is supported along the center line of the inner shell 60 by bearings 65 and extends from the bottom 58 of the outer shell 54 to a point slightly above the inner shell 60. The auger 64 is rotated by a suitable motor 66 to move the material upwardly in the inner shell 60 where it will fall down through the annulus 62, although a portion of the material will fall back through the slots in the auger. It has been found'that when the dry cement and asbestos are mixed in the type of mixer shown in FIG. 7 for about 60 seconds, the materials are thoroughly mixed.

The mixed dry cement and asbestos are then placed in a similar auger type mixer and water is added slowly while the mixer is in operation until the ratio of water to the dry materials isabout 0.125 as noted above. It has been found that the dry cement and asbestos may be suitably mixed with the necessary water by operation of the mixer for a period of 3 to 4 minutes. The resulting composition may be characterized as a compactable plastic material, since it is subject to densification and being formed into a definite shape.

As previously noted, the tool 10 may be used for forming the cement-asbestos composition into a lining. For example, the tool 10 may be used for forming a lining 70 around the interior of a pipe 72 as illustrated in FIGS. 5 and 6. When used in this manner, the tool 10 is maintained centered in the pipe 72 by a plurality of centralizers 76, only one of which is shown, positioned in spaced relation along the length of the shield 53.

Each centralizer 76 may be of any desired construction, such as in the form of a plurality of circumferentially spaced bow springs 78 secured around the outer periphery of the shield 53. A ring 80, as of metal, is secured around the central portions of the bow springs 78 and a ring 82 of bearing material, such as woven or pre-formed brake lining, is bonded around the ring 80 to provide a minimum of friction while in engagement with the inner periphery of the pipe 72.

OPERATION In operation, the tool is positioned in the pipe 72 at the point where it is desired for the lining 70 to begin, and the drive pipe 14 is extended in the direction which the tool is to be moved, with the drive pipe 14 being extended the necessary length, and with the centralizers 76 mounted on the shield 53. The wetted, cement-asbestos composition is fed to the free end of the drive pipe 14 and is blown through the drive pipe 14 with the necessary air pressure to move the composition in a steady stream through the drive pipe 14.

Before the composition reaches the tool 10 from the drive pipe 14, the drive pipe 14 is placed in rotation to thereby also place the tool 10 in rotation as shown by the arrow in FIG. 6. As the composition reaches the flow divider 46 (FIG. 2), the material will be substantially evenly divided into four streams being directed through the conduits 48 to the feed nozzles 50. Inasmuch as the tool 10 is then rotating, the material will be discharged from each feed nozzle 50 in somewhat of a flared pattern, but generally toward the adjacent internal surface of the pipe 72.

A cement-asbestos composition as previously defined will form an immediate bridge between the outer surface of the tool 10 and the inner surface of the surrounding pipe 72. The material discharging from each nozzle 50 will be immediately forced outwardly by the adjacent surface 26, since the surfaces 26 are of increasing radius with respect to the center line of the tool 10, to compact the material against the inner wall of the pipe 72. Simultaneously, the tool 10 is moved lengthwise through the pipe 72, upwardly as viewed in FIG. 5, such that the material discharged from the nozzles 50 is further compacted by reason of the tapered configuration of the surfaces 26 from the end 34 of the tool 10 to the medial portion 32 of the tool. The resulting inner diameter of the lining 70 will be equal to twice the maximum radii of the surfaces 26, which occurs at the medial portion 32 of the body 12.

When the tool 10 is moved lengthwise through the pipe 72 at the correct speed in relation to the amount of the cement-asbestos material being blown through the nozzles 50 and the speed of rotation of the tool 10, no build-up of the cement-asbestos composition will occur above the nozzles 50 (as viewed in FIG. 5), and the resulting liner 70 will be of uniform consistency. Any excess material ejected from the nozzles 50 will simply accumulate in the annulus between the shield 53 and the pipe 72 and will not foul the operation of the tool 10, since the material wili not cling to a surface until it is compacted.

It has been found that the compaction of the material by the tool 10 against the inner wall of the pipe 72, in combination with intense pressure, creates heat which dissipates the water in the form of steam from the composition by virtue of the contact between the outer surfaces of the tool 10 and the material forming the lining 70; thus the water/cement-asbestos ratio of the composition is reduced to about 0.06 or less. The formation of the lining 70 with the extremely low water/cementasbestos ratio referred to above, and the further reduction of such ratio during the formation of the lining, provides a resulting lining having a compressive strength appreciably above that of present day tubular linings. The compressive strength of the resulting lining is uniform when the same tool is used in successive ap- Embodiment of the FIGS. 8-1 1 A modified tool 90, particularly suited for smaller diameter work than the tool 10 previously described, is illustrated in FIGS. 8-1l. The tool basically comprises a body 92, drive pipe 94, and a tubular shield 96.

The body 92 comprises four steel bars or segments 98 (FIG. 11) of identical cross-sectional configuration rigidly secured together in an offset or staggered relation by means of four spacer bars 100. The segments 98 are conveniently formed from four steel bars of originally square cross-sectional configuration secured together in a concentric relationship to facilitate the machining of the exposed surfaces, and then the bars are separated and assembled with the spacers 100 as illustrated in FIG. 11. Each segment 98 is machined to provide an outer surface 102 on the completed body 92 having a smaller radius, with respect to the center line of the body 92, at one side 104 thereof and a larger radius at the opposite side 106 thereof. The radius of each surface 102 increases progressively from the side 104 to the side 106 thereof, and the smaller radius side 104 of each segment 98 is positioned adjacent the larger radius side 106 of the adjacent segment 98 in the direction in which the tool is rotated during use, in the same relationship as in the tool 10 previously described.

As shown in FIG. 8, a medial portion 108 of the body 92 is of the maximum diameter, and then the surface 102 of each segment 98 is tapered radially inwardly toward the upper end 110 of the tool, as well as toward the lower end 112 of the tool to provide upper and lower tapered portions 114 and 116 respectively. The outer diameters of the body 92 at the upper and lower ends thereof are substantially equal.

A threaded bore 118 is provided in the upper end 110 of the body 92 concentrically with respect to the center line of the body, and four ports 120 are formed in the upper end portion 110 of the body providing communication from the bottom of the bore 118 to the outer surface of the body 92. As shown in FIG. 10, each port 120 extends from the bore 118 to the shorter radius side 104 of each of the segments 98 and forms a feed nozzle for material to be applied by the tool 90, much in the same manner as the nozzles 50 previously described in connection with the tool 10. Each port 120 preferably extends at an angle of about 45 with respect to the center line through the body 92.

A tubular sub 122 is threadedly secured in the bore 118 and has four ports 124 in the lower end thereof adapted to mate with the ports 120 in the body 92. Also, a suitable flow divider 126 is secured in the lower end of the sub 122 to direct material flowing through the sub 122 evenly into and through the ports 124 and 120. The drive pipe 94 is threadedly connected to the outer or upper end of the sub 122 and provides a conduit for supplying material to the sub 122.

the tubular shield 96 has an outer diameter substantially equal to the maximum outer diameter of the surfaces 102 of the body 92 at the upper end 110 of the body and is threadedly secured to the upper end 110 of the body 92 to extend concentrically around the sub 122 and the drive pipe 94. A plurality of centralizers 76 of the construction previously described are mounted in spaced relation along the length of the shield 96 to maintain the body 92 centered in a pipe or chamber in which the tool 90 is to be used.

The tool 90 operates in the same manner as the tool prevously described to apply a cement-asbestos composition in the form of a tubular liner around the inner walls of a chamber in which the tool is used. The composition is blown through the drive pipe 94 and is ejected in substantially equal streams through the ports 120 against the adjacent surfaces of a pipe or the like in which the tool is positioned, such that the composition will be compacted by the surfaces 102 as the tool is rotated, and the composition will be further compacted by the tapered portions 114 of the surfaces 102 when the tool is moved lengthwise.

Embodiment of FIGS. 12-14 Another modified tool 130, as shown in FIGS. l214, is particularly suited for forming a lining 132 in a vertically oriented pipe 134 or the like and, further, when the lower end (not shown) of the pipe 134 is closed. The tool 130 basically comprises a body 92a connected to the lower end of a drive pipe 136, and with a shield 138 extending from the upper end of the body 92a concentrically around the drive pipe 136.

The body 92a is constructed in substantially the same manner as the body 92 previously described, by employing the segments 98 interconnected by the spacer bars 100 and providing the tapered outer surfaces 102. The body 92a is modified from that previously described as the body 92 in that no ports are provided in the upper end 140 of the body, and tapered slots 142 are provided in the upper end 140 of the body adjacent the smaller radius side of each of the surfaces 102. The slots 142 may be conveniently formed by machining the end portions of the spacer bars 100.

A shaft or pin 144 is threaded into the bore 118 at the upper end 140 of the body 920 to rigidly secure a tubular connector 146 to the body 92a. The inner periphery of the connector 146 is threaded to receive the upper end of the connecting pin 144, and the outer periphery of the connector 146 is sized to have substantially the same diameter as the maximum outer diameter of the upper end 140 of the body 92a. A plurality of ports 148 are formed through the walls of the connector 146 providing communication from the interior of the connector to the exterior of the connector and forming the equivalent of the feed nozzles 120 of the body 92 previously described. It will be observed that the ports 148 are extended downwardly and outwardly at an angle of about 45 to the center line of the body 92a, and each port 148 provides communication from the interior of the connector 146 to the annulus between the upper end 140 of the body 92a and the inner periphery of the pipe 134 adjacent the smaller radius side 104 of each surface 102, but spaced a short distance from the larger radius side 106 of the adjacent surface 102. The space 150 between the outer end of 5 each port 148 and the adjacent larger radius side 106 of the adjacent surface 102 will not normally be filled with the plastic material being formed into the lining 132, such that any air or steam tending to accumulate around the outer periphery of the body 92a will have access to the slots 142. Vertical holes 152 are bored through the walls of the connector 146 between the ports 148 and communicate at their lower ends with the slots 142 to permit further upward escape of such fluids, as will be further described. It should also be noted that a flow divider 154 is suitably secured in the bore 156 through the connector 146 to direct the plastic material substantially evenly into the ports 148.

The lower end of the shield 138 is threadedly secured around the upper end of the connector 146, and the outer diameter of the shield 138 is substantially equal to the outer diameter ofthe connector 146, as well as the maximum outer diameter of the upper end 140 of the'body 92a. The lower end of the drive pipe 136 is threadedly secured in the upper end of the connector 146 and provides a passageway through which the plastic material is supplied to the body 92a in the same manner as in the embodiments previously described.

A distributing head 158 is interposed in the shield 138 and the drive pipe 136 at some distance above the body 92a. The distributing head 158 is a tubular member, having a bore 160 therethrough for conveying the supply of plastic material, as will be described. A plurality of feed ports 162 provide communication from the bore 160 to ports 164 formed in the shield 138 for directing at least a limited amount of the plastic material into the annulus between the shield 138 and the pipe 134 above the body 92a. Each feed port 162, as shown in FIG. 13, is curved in a direction such that the material ejected therefrom will be directed in a direction generally opposite to the direction of rotation of the tool 130, such that the plastic material will have a minimum tendency to be compacted against the inner periphery of the pipe 134 by virtue of being blown from the ports 162. Four of the ports 162 are preferably provided to provide an even distribution of the material in the annulus between the shield 138 and the pipe 134. A tubular deflector 166 is threadedly secured in the bore 160 immediately below the point of communication between the ports 162 and the bore 160 to deflect a rather minor portion of the plastic material flowing throughthe bore 160 into the ports 162. A plurality of holes 168 are bored vertically through the distributing head 158 between the various ports 162 to provide a further escape of fluids from around the body 92a upwardly through the shield 138.

The tool 130 also includes a plurality of the centralizers 76 of the type previously described secured around the shield 138 above the distributing head 158 to maintain the body 92a centered in the pipe 134 during use of the device, in the same manner as in the embodiments previously described.

the lining 132 is blown through the drive pipe 136, and

the tool is simultaneously rotated and moved upwardly through the pipe 134. The major portion of the In operation, the plastic material to be formed into i plastic material flows downwardly through the bore 160 in the distributing head 158 and on downwardly through the lower section of the drive pipe 136 into the ports 148 to be ejected downwardly and outwardly around the upper end 140 of the body 92a for compaction by the surfaces 102. A fairly minor portion of the plastic material supply is deflected by the deflector 166 in the distributing head 158 through the ports 162 and 164 into the annulus between the shield 138 and the pipe 134. This last mentioned portion of the plastic material supply will not be originally compacted against the inner periphery of the pipe 134 and will simply tend to fall downwardly around the shield 138 to supplement the supply of plastic material being ejected through the ports 148. The additional supply of the plastic material provided by the distributing head 158 permits more leeway in supplying the plastic material to the tool. In other words, the operator has more freedom to supply an excess of the plastic material to the tool to accommodate possible variations in the inner diameter of the pipe 134 or other cylindrical chamber in which the lining 132 is being formed.

As previously noted, the heat generated by compaction of the plastic material by the surfaces 102 normally provides some amount of steam. Also, the plastic material is blown through the nozzles or ports 148 by air pressure, and such fluids need to escape. in the event the lower end of the pipe 134 being lined is closed, these fluids can easily escape upwardly through the slots 142, the vertical holes 152 in the connector 146, the lower section of shield 138, the vertical holes 168 in the distributing head 158, and then on upwardly through the upper portion of the shield 138.

Embodiment of FIGS. and 16 Another slightly modified tool 130a is illustrated in FIGS. 15 and 16 and is also useful in forming a lining around the inner periphery of the vertically oriented pipe 134 or the like. The tool 130a is constructed much in the same manner as the tool 130 previously described in utilizing the shield 138 and drive pipe 136 formed in upper and lower sections interconnected by a slightly modified distributing head 158a. The distributing head 158a is constructed in the same manner as the distributing head 158 previously described, except that the distributing head 158a has a flow divider 170 secured therein immediately below the innerends of the ports .162 to direct all of the plastic material supplied through the drive pipe 136 into and through the ports 162.

The tool 130a also utilizes the body 92a, but the upper end 140 of the body 920 is connected to the lower ends of the drive pipe 136 and shield 138 through a solid connector 172, rather than the tubular connector 146 previously described in connection with the tool 130. The connector 172 is provided with a plurality of holes 174 bored vertically through the portion thereof connected to the lower end of the shield 138 to provide passageways for fluid from the slots 142 to the interior of the lower section of the shield 138 in the same manner as the vertical holes 152 in the connector 146 previously described.

The tool 130a operates in the same manner as the tool 130 previously described, except that all of the plastic material to be compacted by the body 920 into a lining around the inner periphery of the pipe 134 is supplied through the ports 162. As previously noted, the ports 162 are curved to direct the material in a direction substantially opposite to the direction or rotation of the tool, such that the plastic material ejected from the ports 162 will not be compacted against the inner periphery of the pipe 134. Thus, the plastic material ejected from the ports 162 will fall freely through the annulus between the shield 138 and the pipe 134 in a position to be compacted by the body 92a as the tool is rotated and moved upwardly through the pipe 134.

From the foregoing it will be apparent that the present invention provides a highly improved tool for forming a compactable plastic material into a lining. The tool is simple in construction and will have a minimum of wear during use. When the material being formed comprises a cement-asbestos composition, the resulting lining has a compressive strength appreciably above that of present day tube linings made from cement-asbestos compositions or neat cement. The inner diameter of the resulting tubular product will be closely controlled and the inner periphery of the resulting product will be smooth due to the low moisture content of the composition used by the tool in forming the lining and the smooth sides of the tool itself.

Changes may be made in the combination and arrangement of parts or elements as heretofore set forth in this specification and shown in the drawing, it being understood that various changes may be made without departing from the spirit and scope of the invention as defined in the following claims.

What is claimed is: k

l. A tool for forming compactable plastic material into a lining around the interior of a cylindrical chamber, comprising:

a generally cylindrical body having a first end and a second end and being of a size to be rotated and moved lengthwise through the chamber with the second end following the first end, at least a portion of the outer periphery of the body having a radius progressively increasing in a circumferential direction from a smaller radius to a radius substan tially equal to the radius of the inner diameter of the lining to be formed, said increase in radius being in a direction opposite to the direction of rotation of the tool;

a drive pipe connected to the body for rotating the body, moving the body through the chamber and supplying the plastic material'to the body; and

means carried by the body in communication with the drive pipe for depositing the plastic material between the first end of the body and the inner periphery of the chamber, whereby the material will be forced radially outwardly against the inner periphery of the cylindrical chamber by the outer periphery of the body as the body is turned and moved lengthwise through the chamber.

2. A tool as defined in claim 1 wherein the outer periphery of the body is tapered inwardly to a smaller diameter from the medial portion of the body to the first end of the body.

3. A tool as defined in claim 2 wherein the outer periphery of the body is tapered inwardly to a smaller diameter from a medial portion of the body to the second end of the body.

4. A tool for forming compactable plastic material into a lining around the interior of a cylindrical chamber, comprising:

a generally cylindrical body having a first end and a second end and being of a size to be rotated and moved lengthwise through chamber with the second end trailing the first end, the outer periphery of the body being shaped to provide a plurality of surfaces arranged side-by-side circumferentially around the body, each of said surfaces being of a progressively increased radius from one side thereof to the opposite side thereof relative to v the center line of the body, said surfaces being arranged with the smallest radius side thereof adjacent to the largest radius side of the next surface around the body in the direction the body is to be rotated and said surfaces being tapered radially inward from the medial portion of the body to the first end of the body;

a drive pipe connected to the body for rotating the body, moving the body through the chamber and supplying the plastic material to the body, and

means carried by the body in communication with the drive pipe for depositing the plastic material between the first end of the body and the inner periphery of the chamber, in a position to be compacted against said inner periphery by said surfaces as the tool is rotated and moved lengthwise through the chamber.

5. A tool for forming compactable plastic material into a lining around the interior of a cylindrical chamber, comprising:

a generally cylindrical body having a first end and a second end and being of a size to be rotated and moved lengthwise through the chamber with the second end trailing the first end, the outer periphery of the body being shaped to provide a plurality of surfaces arranges side-by-side circumferentially around the body, each of said surfaces being of a progressively increasedradius from one side thereof to the opposite side thereof relative to the center line of the body, said surfaces being arranged with the smallest radius side thereof adjacent to the largest radius side of the next surface around the body in the direction the body is to be rotated, and said surfaces being tapered radially inward from the medial portion of the body to the first end of the body;

a drive pipe connected to the body for rotating the body, moving the body through the chamber and supplying the plastic material to the body; and

a feed nozzle at the first end of the body at the smallest radius side of each of said surfaces in communication with the drive pipe to direct streams of the plastic material radially outward toward the walls of the chamber through which the tool is moved in a position to be compacted against said walls by said surfaces as the tool is rotated and moved lengthwise through the chamber.

6. A tool as defined in claim wherein the body includes four of said surfaces.

7. A tool as defined in claim 5 wherein said nozzles are disposed at an angle of about 45 to the center line of the body.

8. A tool as defined in claim 5 wherein each of said surfaces is also tapered radially inward from a medial portion of the body to a second end of the body.

9. A tool for forming compactable plastic material into a lining around the interior of a cylindrical chamber, comprising:

a generally cylindrical body having a first end and a second end and being of a size to be rotated and moved lengthwise through the chamber with the second end trailing the first end, said body comprising a plurality of identical, circumferentially arranged and interconnected segments, the outer periphery of each of said segments being progressively increased in radius with respect to the center line of the body from one side to the opposite side thereof and with the smaller radius side of each segment being adjacent the larger radius side of the next adjacent segment in the direction of rotation of the tool, each of said segments also being tapered radially inward from the medial portion of the body to the first end of the body;

a drive pipe connected to the body for rotating the body, moving the body through the chamber and supplying the plastic material to the body; and

a feed nozzle at the first end of the body at the smallest radius side of each segment extending at an angle to the center line of the body in communication with the drive pipe to direct a stream of the plastic material radially outward from the body and toward an area opposite the medial portion of the body, whereby the material will be compacted against the walls of the chamber as the body is turned and moved lengthwise through the chamber.

10. A tool as defined in claim 9 wherein the body comprises four of said segments.

11. A tool as defined in claim 9 wherein each of said segments is also tapered radially inwardly from the medial portion of the body toward the second end of the body.

12. A tool as defined in claim 9 characterized further to include:

a flow divider in the drive pipe; and

a flexible conduit connecting the drive pipe at the location of the flow divider to each of the feed nozzles to conduct the plastic material from the drive pipe to the feed nozzles.

13. A tool as defined in claim 9wherein the feed nozzles extend at an angle of about 45 to the centerline of the body.

14. A tool as defined in claim 9 wherein each of said segments comprises a quarter section of a pipe and plates interconnecting said sections at the first and second ends of the body in a non-symmetrical arrangement to provide said variations in said radii circumferentially around the body.

15. A tool as definedin claim 14 characterized further to include reinforcing plates secured around the inner periphery of each of said sections.

16. A tool as defined in claim 9 characterized further to include a tubular shield secured to the first end of the body in alignment with the center line of the body and having an outer diameter substantially equal to the maximum diameter of the first end of the body.

17. A tool as defined in claim 16 characterized further to include a plurality of'centralizers secured around the shield in spaced relation along the length of the shield sized to engage the surfaces of the chamber and retain the body centered in'the chamber.

22. A tool for forming compactable plastic material into a lining around the interior of a vertically oriented cylindrical chamber, comprising:

a generally cylindrical body having an upper end and 18. A tool as defined in claim 9 wherein each of said segments is a metal bar.

19. A tool as defined in claim 18 wherein said nozzles comprise ports formed in said bars.

20. A tool for forming compactable plastic material a l w d and ng of a Size to be rotated and into a lining around the interior of a vertically oriented moved p y through the Chamber, Said dy li d i l h b i i comprising a plurality of identical, circuma generally cylindrical body having an upper end d ferentially arranged and interconnected segments,

a lower end and being of a size to be rotated and the outer Periphery of each of Said Segments being moved upwardly through the chamber, the Outer l0 progressively increased in radius with respect to periphery of the body being shaped to provid a the center lme of the body from one side to the opplurality of Surfaces arranged side by side circum posite side thereof and with the smaller radius s de ferentially around the body, each of said surfaces f each Segment f g adjacent th larger rad us being of a progressively increased radius from one side of the next ad acent segmentmthe direction side thereof to the opposite side thereof relative to ofrotanon of the tooli each of Sald segmerllts also the center line of the body, said surfaces being arh tapered radially Inward m the medlal eeeeee with the emeneee eeeiee eeee eheeeef a23sat azaatarraasrsazsatmthe jacent to the largest radius side of the next surface Smallest radius Side of each Segment extending at around the y in the directloh the body is to be 20 an angle to the center line of the body to direct a rotated, and Said Surfaces being tapered radially stream of the plastic material radially outward inward from the medial portion of the body to the f the body and toward an area opposite the pp end of the body; and medial portion of the body in a position to be coma distributing head Supported above the y pacted against the inner periphery of the chamber centrically with the center line of the body, said as h bod i t rned and moved upwardly through head having a plurality of circumferentially spaced h h b plastic material feed ports therein arranged to a d i i secured t th upper d f h b d f deposit the material evenly around the inner moving the body and supplying the plastic material periphery of the chamber where the material will to the nozzles; be compacted against said inner periphery of the a distributing head interposed in the drive pipe above body as the body is rotated and moved upwardly the body, said head having a plurality of circumthrough the champer; ferentially spaced plastic material feed ports wherein the head is supported from the body by a therein communicating with the interior of the drive pipe and a tubular shield extending concendrive pipe to supply an additional quantity of the trically around the drive pipe between the head material to the chamber; and and the upper end of the body, aid hield having a tubular shield extending concentrically around the an outer diameter substantially equal to the maxdrive pip between the fl d the dy an h i outer di f h upper d f h b d ing an outer diameter substantially equal to the and characterized further to include means formmaximum outer diameter of the pp end of the ing passages from the upper end portion of the to direct said additional quantity Of material body below the shield through the shield and the head for the escape of fluid evolved during the between the body and the inner periphery of the chamber.

23. A tool as defined in claim 22 characterized further to include means forming air passages from the outer periphery of the body below the nozzles to the interior of the shield and vertically through the head between said feed ports.

compaction of the plastic material against the inner periphery of the chamber.

21. A tool as defined in claim 20 wherein said feed 4 ports are curved to eject the plastic material from the head in a direction generally opposite to the direction of rotation of the head. 

1. A tool for forming compactable plastic material into a lining around the interior of a cylindrical chamber, comprising: a generally cylindrical body having a first end and a second end and being of a size to be rotated and moved lengthwise through the chamber with the second end following the first end, at least a portion of the outer periphery of the body having a radius progressively increasing in a circumferential direction from a smaller radius to a radius substantially equal to the radius of the inner diameter of the lining to be formed, said increase in radius being in a direction opposite to the direction of rotation of the tool; a drive pipe connected to the body for rotating the body, moving the body through the chamber and supplying the plastic material to the body; and means carried by the body in communication with the drive pipe for depositing the plastic material between the first end of the body and the inner periphery of the chamber, whereby the material will be forced radially outwardly against the inner periphery of the cylindrical chamber by the outer periphery of the body as the body is turned and moved lengthwise through the chamber.
 2. A tool as defined in claim 1 wherein the outer periphery of the body is tapered inwardly to a smaller diameter from the medial portion of the body to the first end of the body.
 3. A tool as defined in claim 2 wherein the outer periphery of the body is tapered inwardly to a smaller diameter from a medial portion of the body to the second end of the body.
 4. A tool for forming compactable plastic material into a lining around the interior of a cylindrical chamber, comprising: a generally cylindrical body having a first end and a second end and being of a size to be rotated and moved lengthwise through chamber with the second end trailing the first end, the outer periphery of the body being shaped to provide a plurality of surfaces arranged side-by-side circumferentially around the body, each of said surfaces being of a progressively increased radius from one side thereof to the opposite side thereof relative to the center line of the body, said surfaces being arranged with the smallest radius side thereof adjacent to the largest radius side of the next surface around the body in the direction the body is to be rotated and said surfaces being tapered radially inward from the medial portion of the body to the first end of the body; a drive pipe connected to the body for rotating the body, moving the body through the chamber and supplying the plastic material to the body, and means carried by the body in communication with the drive pipe for depositing the plastic material between the first end of the body and the inner periphery of the chamber, in a position to be compacted against said inner periphery by said surfaces as the tool is rotated and moved lengthwise through the chamber.
 5. A tool for forming compactable plastic material into a lining around the interior of a cylindrical chamber, comprising: a generally cylindrical body having a first end and a second end and being of a size to be rotated and moVed lengthwise through the chamber with the second end trailing the first end, the outer periphery of the body being shaped to provide a plurality of surfaces arranges side-by-side circumferentially around the body, each of said surfaces being of a progressively increased radius from one side thereof to the opposite side thereof relative to the center line of the body, said surfaces being arranged with the smallest radius side thereof adjacent to the largest radius side of the next surface around the body in the direction the body is to be rotated, and said surfaces being tapered radially inward from the medial portion of the body to the first end of the body; a drive pipe connected to the body for rotating the body, moving the body through the chamber and supplying the plastic material to the body; and a feed nozzle at the first end of the body at the smallest radius side of each of said surfaces in communication with the drive pipe to direct streams of the plastic material radially outward toward the walls of the chamber through which the tool is moved in a position to be compacted against said walls by said surfaces as the tool is rotated and moved lengthwise through the chamber.
 6. A tool as defined in claim 5 wherein the body includes four of said surfaces.
 7. A tool as defined in claim 5 wherein said nozzles are disposed at an angle of about 45* to the center line of the body.
 8. A tool as defined in claim 5 wherein each of said surfaces is also tapered radially inward from a medial portion of the body to a second end of the body.
 9. A tool for forming compactable plastic material into a lining around the interior of a cylindrical chamber, comprising: a generally cylindrical body having a first end and a second end and being of a size to be rotated and moved lengthwise through the chamber with the second end trailing the first end, said body comprising a plurality of identical, circumferentially arranged and interconnected segments, the outer periphery of each of said segments being progressively increased in radius with respect to the center line of the body from one side to the opposite side thereof and with the smaller radius side of each segment being adjacent the larger radius side of the next adjacent segment in the direction of rotation of the tool, each of said segments also being tapered radially inward from the medial portion of the body to the first end of the body; a drive pipe connected to the body for rotating the body, moving the body through the chamber and supplying the plastic material to the body; and a feed nozzle at the first end of the body at the smallest radius side of each segment extending at an angle to the center line of the body in communication with the drive pipe to direct a stream of the plastic material radially outward from the body and toward an area opposite the medial portion of the body, whereby the material will be compacted against the walls of the chamber as the body is turned and moved lengthwise through the chamber.
 10. A tool as defined in claim 9 wherein the body comprises four of said segments.
 11. A tool as defined in claim 9 wherein each of said segments is also tapered radially inwardly from the medial portion of the body toward the second end of the body.
 12. A tool as defined in claim 9 characterized further to include: a flow divider in the drive pipe; and a flexible conduit connecting the drive pipe at the location of the flow divider to each of the feed nozzles to conduct the plastic material from the drive pipe to the feed nozzles.
 13. A tool as defined in claim 9 wherein the feed nozzles extend at an angle of about 45* to the centerline of the body.
 14. A tool as defined in claim 9 wherein each of said segments comprises a quarter section of a pipe and plates interconnecting said sections at the first and second ends of the body in a non-symmetrical arrangement to provide said variations in said radii circumferentially arouNd the body.
 15. A tool as defined in claim 14 characterized further to include reinforcing plates secured around the inner periphery of each of said sections.
 16. A tool as defined in claim 9 characterized further to include a tubular shield secured to the first end of the body in alignment with the center line of the body and having an outer diameter substantially equal to the maximum diameter of the first end of the body.
 17. A tool as defined in claim 16 characterized further to include a plurality of centralizers secured around the shield in spaced relation along the length of the shield sized to engage the surfaces of the chamber and retain the body centered in the chamber.
 18. A tool as defined in claim 9 wherein each of said segments is a metal bar.
 19. A tool as defined in claim 18 wherein said nozzles comprise ports formed in said bars.
 20. A tool for forming compactable plastic material into a lining around the interior of a vertically oriented cylindrical chamber, comprising: a generally cylindrical body having an upper end and a lower end and being of a size to be rotated and moved upwardly through the chamber, the outer periphery of the body being shaped to provide a plurality of surfaces arranged side-by-side circumferentially around the body, each of said surfaces being of a progressively increased radius from one side thereof to the opposite side thereof relative to the center line of the body, said surfaces being arranged with the smallest radius side thereof adjacent to the largest radius side of the next surface around the body in the direction the body is to be rotated, and said surfaces being tapered radially inward from the medial portion of the body to the upper end of the body; and a distributing head supported above the body concentrically with the center line of the body, said head having a plurality of circumferentially spaced plastic material feed ports therein arranged to deposit the material evenly around the inner periphery of the chamber where the material will be compacted against said inner periphery of the body as the body is rotated and moved upwardly through the champer; wherein the head is supported from the body by a drive pipe and a tubular shield extending concentrically around the drive pipe between the head and the upper end of the body, said shield having an outer diameter substantially equal to the maximum outer diameter of the upper end of the body, and characterized further to include means forming passages from the upper end portion of the body below the shield through the shield and the head for the escape of fluid evolved during the compaction of the plastic material against the inner periphery of the chamber.
 21. A tool as defined in claim 20 wherein said feed ports are curved to eject the plastic material from the head in a direction generally opposite to the direction of rotation of the head.
 22. A tool for forming compactable plastic material into a lining around the interior of a vertically oriented cylindrical chamber, comprising: a generally cylindrical body having an upper end and a lower end and being of a size to be rotated and moved upwardly through the chamber, said body comprising a plurality of identical, circumferentially arranged and interconnected segments, the outer periphery of each of said segments being progressively increased in radius with respect to the center line of the body from one side to the opposite side thereof and with the smaller radius side of each segment being adjacent the larger radius side of the next adjacent segment in the direction of rotation of the tool, each of said segments also being tapered radially inward from the medial portion of the body to the upper end of the body; a feed nozzle at the first end of the body adjacent the smallest radius side of each segment extending at an angle to the center line of the body to direct a stream of the plastic material radially outward from the body and toward an area opposite tHe medial portion of the body in a position to be compacted against the inner periphery of the chamber as the body is turned and moved upwardly through the chamber; a drive pipe secured to the upper end of the body for moving the body and supplying the plastic material to the nozzles; a distributing head interposed in the drive pipe above the body, said head having a plurality of circumferentially spaced plastic material feed ports therein communicating with the interior of the drive pipe to supply an additional quantity of the material to the chamber; and a tubular shield extending concentrically around the drive pipe between the head and the body and having an outer diameter substantially equal to the maximum outer diameter of the upper end of the body to direct said additional quantity of material between the body and the inner periphery of the chamber.
 23. A tool as defined in claim 22 characterized further to include means forming air passages from the outer periphery of the body below the nozzles to the interior of the shield and vertically through the head between said feed ports. 